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The self-assembly of amphiphilic macromolecules end-grafted to a plane surface is studied using mean-field theory and computer simulations. Chain backbones are built from hydrophobic groups, whereas side groups are hydrophilic. The brush is immersed in a solvent, which can be good or poor, but on average is not far from θ conditions. It is demonstrated that the strong amphiphilicity of macromolecules at a monomer unit level leads to their self-assembly into a system of strands with a 2D hexagonal order in a cross-section parallel to the grafting plane. The structure period is determined by the length of side groups. In theory, this effect is explained by the orientation of strongly amphiphilic monomer units at a strand/solvent boundary that leads to an effective negative contribution to the surface tension. Computer simulations with molecular dynamics (MD) are used for a detailed study of the local brush structure. The aggregation number of strands grows with the increase of the grafting density and side group length.

The main feature of amphiphilic homopolymers is the effective surface activity of their monomer units, due to which, in selective solvent, they can aggregate into various structures, some of which resemble those formed by low-molecular surfactants and are prospective in many practical applications. The paper aims to address dilute solutions of amphiphilic homopolymers and to reveal the features of their self-assembly depending on the solvent selectivity and the relative solvent quality for solvophobic and solvophilic groups of monomer units. The calculations, performed in the framework of dissipative particle dynamics (DPD), allowed us to find various morphological aggregates, to analyze details of their structure, and to determine the field of their stability. The results are presented in the form of a diagram and described in the framework of original analytical theory.

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